Frederick Schauer (Harvard University - John F. Kennedy School of Government) has posted Why Precedent in Law (and Elsewhere) is Not Totally (or Even Substantially) About Analogy on SSRN. Here is the abstract:
Cognitive scientists and others who do research on analogical reasoning often claim that the use of precedent in law is an application of reasoning by analogy. In fact, however, law's principle of precedent is quite different. The typical use of analogy, including the use of analogies to earlier decisions in legal argument, involves the selection of an analog from multiple candidates in order to help make the best decision now. But the legal principle of precedent requires that a prior decision be treated as binding, even if the current decision-maker disagrees with that decision. When the identity between a prior decision and the current question is obvious and inescapable, precedent thus imposes a constraint quite different from the effect of a typical argument by analogy. The importance of this is not so much in showing the a common claim in the psychological and cognitive science literature is mistaken, but that the possibility of making decisions under the constraints of binding precedent is itself an important form of decision-making that deserves to be researched in its own right.
And some more from the text:
Whereas analogical reasoners are widely understood to have a choice among various candidate source analogs, and whereas it is often argued that experts can be distinguished from novices by the way in which they retrieve their source analogs on the basis of structural rather than superficial similarities to the target (Gentner, 1983; Gentner, Rattermann, & Forbus, 1993; Holyoak & Koh, 1987), such freedom is ordinarily absent with respect to constraint by precedent. Justice Stewart would have thought bizarre the suggestion that finding another earlier case could let him avoid the constraints of Griswold, just as Justice White would surely have laughed at the idea that feeling constrained by Miranda was simply a function of not having selected the best source case. Although it is true that on occasion creative and effective advocates can persuade a court to see a case or an issue in an entirely new light, far more often a previous decision about issue X looms so large that it is implausible for a judge to avoid that decision by maintaining that the current case is about Y and not about X. . So although, in a very attenuated technical sense, no 2004 forest green Toyota Corolla is the same car as some other 2004 forest green Toyota Corolla, it would be peculiar to criticize one owner of such a car from saying to another owner that "I have the same car." So too here. Any two previous cases, instances, acts, or events are in some respects different, but in reality their equation is often inescapable.
Another great paper from Schauer. Highly recommended! Download it while its hot!
Source:
http://lsolum.typepad.com/legaltheory/2007/08/schauer-on-prec.html
